Method of making burners



Dec. 14, 1937. L M, 2,102,530

METHOD OF MAKING BURNERS Filed May 29, 193 2 Shets-Sheet 1 iNVENTOR CkrzIrlopIwrLbfirda/ick.

ATTORNEYS Dec. 14, 1937.

C. L. HARDWICK METHOD OF MAKING BURNERS Filed May 29, 1956 2 Sheets-Sheet 2 FMMA ATTORNEYS Patented Dec. 14, 1937 I E STATES.

@ATENT Q E' METHOD OF MAKING BURNERS Christopher L. Hardwick, Cleveland, Tenn; Application May 29, 193B, Serial-No. 182,604

3 Claims. (01.229200 I This invention relates to a method of casting one piece burners having a continuous relatively narrow annular horizontally arranged combustion. opening or slot.

According to present practice such burners are cast with solid walls or sides, and the combustion slot or opening is then formed with a cutting tool, such as disclosed in my prior Patent No.

2,022,857, granted December 3, 1935. This machine method has been practiced due to the fact that it has been found impossible to form the combustion slot by ordinary casting methods. The gas slot is relatively narrow, that is, approximately T 6 of an inch in width, thus making it impracticable to employ a baked sand core having a sufillciently thin projection or flange to form a slot of such narrow width, due to the fact that the flange or projection would break down when the molten metal is poured.

An object of the present invention is to overcome the foregoing objections by providing a method whereby the combustion slot can be formed simultaneously with the casting operation.

Other and more specific objects and advantages of the invention will be apparent from the following description considered with the accompanying drawings, in which:

Figure 1 is a side elevation of a'burner casting having an annular combustion slot formed therein according to my invention;

Figure 2 is a sectional view through a mold showing the novel core and the slotted casting therein, the transverse core being omitted;

Figure 3 is a plan view of-the lower or drag portion of the mold, the casting and cores being shown in section, the section being taken on the mold junction line 3--3 of Figure 2;

Figure 4 is a perspective view of the main core with the slot forming auxiliary core member in place thereon; and

Figure 5 is a perspective view of the slot-forming or auxiliary transverse core member.

Referring more particularly to the drawings B denotes a gas burner made according to my improved method, and adapted for use with gas stoves, hot air furnaces, steam and hot water boilers. The burner B consists of a hollow integral casting I, one end of which forms an elon- 55 lar slot 5, where combustion occurs. A through gated mixing tube 2 and the other end of which opening 6, "surrounded by the wall of chamber dyinsures an adequate supply of secondary air tothe flame,

' The slot 5 is formedduringand simultaneously with the casting of the burner. Thus a baked sand core I'of subStantiaIly the same size and contour as casting I, is suitably positioned in a two part fiask or mold 8 for the conventional pouring operation. In the present embodiment the flask or mold 8 comprises a lower half or drag portion 9, and an upper half or cope portion EU, as illustrated in Figures 2 and 3. A second and intersecting baked sand core II, shown in Figure 3 is also inserted in the flask for an obvious purpose. It will be noted that the body o burner portion l2 of the core I, carries a rin shaped auxiliary core member I3, which is designed to keep the molten metal from contacting with that area of the sand core immediately back of or adjacent to the space comprising the slot 5 in the completed casing I, thus keeping this space open during the casting operation. The ring-shaped auxiliary core member I3, which is made of any suitable non-combustible material, which is not sufficiently fragile to become broken or distorted by flowing metal, is preferably slipped over the mouth of the sand core I after the core has been baked, as best illustrated in Figures 3 and 4 of the drawings. Rings I3 made of asbestos paper have proven very satisfactory because rings of this material, are not only highly resistant to heat, and sufiiciently strong to withstand the strains and stresses incident to the casting operation, but can be readily removed after the casting I has been made. The core member I3, must project from the baked sand core I, and in reality constitutes a. relatively thin flange. Such a thin flange formed of baked sand has been found to be utterly impracticable due to the fragile nature of baked sand.

It will be understood that when the molten metal is poured into the gates or pouring openings I4 and I5 of mold 8, the metal will flow about the cores 1 and II to form a casting I, having the slot 5 formed therein. The ring-shaped noncombustible auxiliary core member I3 remains unbroken and undistorted by the molten metal and consequently the slot 5 will be acccurately formed. After the casting has cooled and the baked cores I and II broken down and the sand poured out of the casting, in a manner well known to workers in the art, the ring-shaped slot forming member I3 is removed. Any suitable hand tool may be employed for removing the ring I3 from the casting. In addition to functioning as an auxiliary core member the ring l3 serves to anchor the core in the sand of the flask or mold. Having thus described my invention, what I claim is:

1. The method of casting round burners having a hollow body and a relatively thin annular com- 7 bustion slot comprising the steps of forming a baked sand core having the outline of said body, I

auxiliary core member of strong non-combustible material on one edge of said sand core and extending beyond the side wall thereof and placing the same in the mold with the greater portion of the flat face of the auxiliary core spaced from the sand of the mold and the edges embedded in the sand for supporting the core whereby when metal'is cast in said mold, the space occupied by the thickness of the flat Washer shaped core will constitute a slot in one wall of the body. 7 I

3. The method of casting round burners having a hollow body portion and a relatively thin annular combustion slot intersecting one wall, comprising thelsteps of for ming a'baked sand core having the outline of said body, and placing a second sand core transversely through an opening. in said first. core and spaced therefrom,'plac- 7 ing a flat washer shaped auxiliary core member of strong non-combustible material on one edge of said first sand core and spaced from the second transverse sand core and placing the same in the mold with the greater portionof the flat face of the auxiliary core spaced from the sand of the mold and a small portion of the same embedded in the sand for supporting the core whereby when the metal is cast in said mold the space occupied by the thickness of the fiat washer shaped core will constitute a slot in one wall of the body. r r

. CHRISTOPHER L. I-LARDWICK. 

